Port problem

[Ormha]

Hi everyone!
Recently, I was interested by making a CSS server, so find this fabulous web site. I have follow each of the instructions in the tutorial, but something's wrong and I think it is the port.

I have tried many things, but nothing works... and well, I tried this command : srcds.exe -console -game cstrike +map de_dust2 -maxplayers 16 -autoupdate +ip "external IP" -port 27015
And this doesn't work. It says that He couldn't allocate dedicated server to this UDP port.

By the way, my modem's model is this : 2701HG

If someone can help me, I would really appreciate it!
Thanks!

[[TgA] ATI]

This is what i use and it works:
-console -game cstrike -autoupdate +maxplayers 20 +map de_dust3 -port 27015

You need to go into your windows firewall and froward it there also. Your ISP may not allow you to forward ports, my old ISP wouldn't let me. Lastly log into your modem and tell to foward 27015 to the internal ip of the CSS server like 192.168.1.2 or what ever it may be. If you have a router do the same there and set a static internal ip to the server. to find out all the server info go to start - run- cmd - ipconfig /all
I didnt need to ever go into my modem it did it all from my router. let me know if this helps.

[Ormha]

Hi,
I tried the command but nothing happend... it always only me that is able to go on my server. No one else, none of my friends. They are all receive, "server is not responding".
I temporary desactivate my firewall et tried all what you say, but nothing work.

I don't have a modem, my router provide me the internet access as well a home network. I don't have a static IP... but dynamic, it will change every time I'm unconnected to the network.

Thanks in advance!

[Drocona]

Replace the word "modem" with "router" in ATI's post and it is correct.